Fecal immunochemical test

Fecal Immunochemical Test (FIT) is a diagnostic technique that examines stool samples for traces of non-visible blood, which could potentially indicate conditions including bowel cancer. Symptoms which could be caused by bowel cancer and suggest a FIT include a change in bowel habit, anaemia, unexplained weight loss, and abdominal pain. By using a random forest classification model, sensitivity can be increased.

Note: Blood in stools does not always mean the presence of bowel or anal cancer, it could be from other bowel diseases such as ulcerative colitis, Crohn's disease or even hemorrhoids.

A 2022 UK guideline recommends the use of a FIT threshold of fHb ≥10 μg Hb/g to select patients with symptoms for an urgent referral for colorectal cancer investigation.